Multi-color pens are well known and have been in wide spread use for many years. For example, a U.S. Pat. No. 4,692,046 of Lan discloses a pen containing multi-color cores located in different tubes housed in the pen body. The colors can be optionally selected for use readily using a specially designed turnable knob having a projected edge in cam contact with the top end of the core-receiving tubes. The top end of the core-receiving tube is pushed down-ward for use, when the turnable knob is rotated to enable a person to select a color core quickly and readily.
A more recent development in multi-color pens with storage functions is disclosed in a U.S. Pat. No. 7,347,638 of Lin. As disclosed, the pen with storage function includes a pen holder, an end of which includes a storage device, enabling a USB (Universal Serial Bus) connector of the storage device to protrude out of the penholder, for connecting with an external computer to download data. A chosen place on a surface of the penholder is installed with a light pervious casing, and an inner wall of the penholder, corresponding to the light pervious casing, is surrounded with at least one solar power flashing LCD (Liquid Crystal Display), such that when the LCD has absorbed sufficient solar energy, commercial prints on the LCD can be flashingly displayed.
Notwithstanding the above, it is presently believed that there is a need and a potential commercial market for a multi-color pen that includes a plurality of useful implements. There should be a market for such devices because they can provide multiple elements in a convenient and relatively small space and enable a user to use the pen for various purposes.